1. Field of the Invention
The present invention relates to a storing apparatus, and more particularly to a storing apparatus equipped with a flash memory.
2. Description of the Related Art
In recent years, a semiconductor storing apparatus having a large storage capacity, such as a flash memory, has been used in various devices in order to store data.
A flash memory performs the writing and the reading of data on a unit basis of what is called a block, and may happen to include a defective block to which data writing cannot effected normally owing to the manufacturing process of the memory or a subsequently happened cause. Accordingly, the flash memory is arranged to have a portion of a storage area thereof as a substitute block for such a defective block so that the data to be written into the defective block is written instead into the substitute block. Moreover, the technique of informing a user of a warning when the remaining amount of substitute blocks becomes smaller than a set value was also proposed (see, for example, Japanese Patent Application Laid-Open Publication No. 2003-085054).
A detachable storing apparatus, such as a memory card, equipped with a flash memory is used to be mounted on various host devices. A host device has its specific type of data to be treated, size of data to be written, data rate, and the like, which are different from those of other host devices, respectively. Even if the lowering of the remaining amount of substitute blocks is, consequently, warned in the conventional manner, it may happen depending on the host device that the remaining amount of the substitute blocks is really not enough for the capacity to be secured at the time of writing data to cause a writing error.
For example, in the case of a host device in which the amount of data to be written at one time is large, the probability of using many substitute blocks at one time of writing is higher than that of a device in which the amount of data to be written at one time is small.